The KLT Filter as a method of "Smart Averaging" to improve SNR in real-time cine MRI
نویسندگان
چکیده
Introduction: It has been shown that Karhunen-Loeve transform (KLT) filter can be applied to real-time dynamic cardiac MR images to improve the signal-to-noise ratio (SNR) without compromising the boundary sharpness [1]. KLT filtering takes advantage of temporal redundancy and can be viewed as a kind of “smart averaging” without the need for image registration. Since cardiac motion is quasi-periodic, the temporal redundancy of real-time cardiac MR images increases with the number of cardiac cycles included. Therefore, acquisition of a longer series of images covering more cycles can be used to improve the performance of the KLT filter, resulting in greater SNR gain. In this abstract, we show how the SNR of KLT filtered images increases with the number of frames in real-time cine imaging of the heart.
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